Besides functioning as a USB host, an OTG device can also function as a USB device. For example, if the device functions as a USB mass-storage device, a PC or other USB host will see the OTG device as a drive. OTG requires support for switching roles (host/device).
I have some links to info about OTG and embedded USB hosts here:
and Jans book “USB complete” explains USB very well
— On Sun, 12/12/10, Jan Axelson jan@lvr.com wrote:
> From: Jan Axelson jan@lvr.com > Subject: Re: [beagleboard] Development Steps For USB OTG > To: beagleboard@googlegroups.com > Date: Sunday, December 12, 2010, 9:39 AM > > > I understand the BeagleBoard has USB OTG capabilities, but I’m not > > exactly sure I understand how to use it. > > > > Conceptually, can (any?) usb device that outputs data (mouse, webcam, > > etc) connect to the beagle? > > Yes, if the OS has a driver for the device, applications can access the device. Communicating with devices requires only USB host capability, not OTG. > > > In general, what does it mean that there is hardware support for OTG, > > and what does leave for the software developer to do? > > If you want to access popular device types, the OS is likely to already have class drivers. I have a few Linux examples here: > > http://www.lvr.com/beagleboard.htm > > Besides functioning as a USB host, an OTG device can also function as a USB device. For example, if the device functions as a USB mass-storage device, a PC or other USB host will see the OTG device as a drive. OTG requires support for switching roles (host/device). > > I have some links to info about OTG and embedded USB hosts here: > > http://www.lvr.com/embedded_host.htm > > Jan > – You received this message because you are subscribed to the Google Groups “Beagle Board” group. > To post to this group, send email to beagleboard@googlegroups.com. > To unsubscribe from this group, send email to beagleboard+unsubscribe@googlegroups.com. > For more options, visit this group at http://groups.google.com/group/beagleboard?hl=en.